Does short-term intraoperative electrical stimulation enhance nerve regeneration following peripheral nerve repair? A systematic review and meta-analysis.

BACKGROUND

Although intraoperative electrical nerve stimulation appears to be a promising neuroenhancing adjunct to peripheral nerve repair, insight into its effects on nerve regeneration is essential to advocate its application in clinical settings.

OBJECTIVE

This study examined whether electrical stimulation during microsurgical repair of peripheral nerve injury results in enhanced nerve regeneration compared to suture repair alone in experimental animals.

METHODS

A systematic search in Embase, MEDLINE, Web of Science, and Google Scholar databases was performed from inception to March 22, 2024. The search included animal studies assessing outcomes following peripheral nerve repair with and without intraoperative electrical stimulation. Outcomes were subdivided into 4 categories: motor function, sensory function, electrophysiology, and histology. We calculated standardized mean differences and combined these using random effects models to estimate the overall effect. The risk of bias was assessed using the SYRCLE tool.

RESULTS

From 3615 references, 21 articles were included. Thirteen studies evaluated motor functional outcomes and showed that electrical stimulation improved functional index, muscle mass, muscle force, footstep accuracy, footprint, and joint angle measures. Six studies examined sensory function and found that electrical stimulation improved mechanical algesimetry. Nine studies assessed electrophysiology outcomes. Although conduction velocity did not differ between the groups, electrical stimulation resulted in a higher amplitude and lower latency. Twenty studies evaluated the histological outcomes and demonstrated increased axon count and myelin thickness, whereas axon diameter and G-ratio did not differ.

DISCUSSION

The results suggest that intraoperative electrical stimulation following peripheral nerve repair accelerates and improves nerve regeneration compared with nerve repair alone.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42023455066.